The battling Blanche Ely High School students only ceased when zapped with a Taser, officials said.
There were no weapons involved. Johnson and Robinson, briefly stunned by the Taser, were examined by doctors before being booked into jail.
Veda Coleman-Wright, spokeswoman for the Broward Sheriff's Office, said the fight broke out shortly after school started at the Pompano Beach high school.
School resource deputy Jeffery Mallory noticed a group forming as students mustered for class.
"Instinct told him to get over there and see what was going on," Coleman-Wright said.
"They were going at it, and they weren't stopping."
The girls ignored Mallory's commands to stop, and refused to be pulled apart.
Another unidentified sheriff's deputy came upon the scene, Coleman-Wright said. "When he saw that the girls were continuing to fight, he immediately tried to gain control of what could have been a violent situation and deployed the Taser," she said.
The pair ceased fighting after being stunned, and were taken to the hospital — standard Sheriff's Office procedure when a Taser is used — and were medically cleared and booked into jail. They told deputies they had been fighting over a boy.
The fight was brief. "It was over fairly quickly," Coleman-Wright said.
Last Wednesday, Hollywood police arrested 25 people after a lunchtime brawl at South Broward High School.